硫化钠蒸发浓缩工艺的现状与展望

讨论了目前中国硫化钠（俗名硫化碱）生产过程中蒸发浓缩使用的各种设备，并详细阐述了各种蒸发器的结构特点、使用方法和适用范围，为中国硫化钠生产企业选择蒸发方式提供参考，并指出中国硫化钠的蒸发工序今后应向技术型、经济型、环保型方向发展。     

薄膜蒸发器在硫化碱蒸发过程中的应用

介绍了薄膜蒸发器在硫化碱蒸发工序中的应用情况。与以前的蒸发器比较，成品碱含量由60％提高到65％，年节约成本（蒸发工作）148万元，废气排放达标。     

碱化碱溶液浓缩方法

本专利是关于用离心薄膜蒸发器连续蒸发浓缩硫化碱溶液的方法。目前硫化碱溶液的浓缩主要有两种方式:浓缩锅的间歇浓缩和离心薄膜蒸发器与浓缩锅组合的联合浓缩。前者需要劳动力多、生产笨重、落后;后者因蒸发器易结垢,需要定期停工检修。此外,用离心薄膜蒸发器连续浓缩低浓度硫化碱溶液时,为了避免因温度高产品质量下降的缺点,在130毫米汞柱的真空下操作,这样一来产品质量得到保证,但因沸点降低,硫化碱一经浓缩到40~45%(重量),器内就会结疤,不能连续操作。为了解决上述问题,研究了供料浓度和蒸发器内溶液浓度随时间变化关系。     

降低硫化碱蒸发煤耗的探讨与实践

介绍了降低硫化碱蒸发煤耗的一些技术措施,在20000t·a~(-1)硫化钠生产线的蒸发工序中使用导热油炉,板式蒸发器,DCS集散控制系统,310S不锈钢防腐材料,并采取提高蒸发器安装高度、改进真空系统、进料出料控制方法、改进完成液浓度的确认、提高进料温度等一系列技术改进措施,将蒸发煤耗降低到了220 kg以下,达到了降低硫化碱蒸发煤耗的效果。     

烧碱三效顺流蒸发过程的连续化自动控制

烧碱蒸发工序是氯碱厂生产的咽喉工序,是将含NaoH 10％左右的电解液蒸发浓缩成成品液碱。此工序直接影响成品碱的产量、质量以及能耗,在生产过程中由于有大量的颗粒盐析出,所以易造成工艺管道、阀门以及一些测量仪表的堵塞。我厂烧碱蒸发在扩建后采用了三效顺流部分强制循环新工艺。过去一直为减少盐晶堵塞采用人工操作的间歇式生产方式,这不仅影响了每一效蒸发器的蒸发能力、能耗,而且影响     

硫化碱列管蒸发系统带液现象分析与改进措施

目前,中国硫化碱行业普遍采用列管蒸发系统,但是大多数硫化碱生产厂家反映,采用该蒸发系统存在蒸发带液现象。针对当前硫化碱行业采用列管蒸发系统存在的蒸发带液问题,对蒸发器蒸发室尺寸、除沫器形式、进料口位置、循环管出口位置等蒸发器结构进行了分析,以及对蒸发系统的真空度、进料速度、蒸发底液、蒸发浓度等控制条件进行了讨论,找出了产生蒸发带液现象的原因,从设备设计结构和工艺条件控制方面提出了改进的具体措施。     

导热油炉加热旋转薄膜蒸发器在硫化碱蒸发中的应用

导热油炉加热旋转薄膜蒸发器是一种新型的硫化碱生产的关键设备，它由导热油炉与旋转薄膜蒸发器两部分组成。它的使用可使硫化碱蒸发工段实现连续化生产，且可减轻劳动强度，改善劳动条件，提高生产效率，稳定产品质量，节约能源，降低消耗，又不污染环境。     

48%烧碱蒸发装置运行总结

介绍了薄膜蒸发器在烧碱浓缩中的应用,阐述了质量分数为48%的烧碱蒸发装置的进料、出料、冷碱、真空系统的工艺及运行情况,72 h考核验收及产品质量分析显示,达到了预期目标.     

6万t/a 48%烧碱板式蒸发生产技术

介绍了阿法拉伐的板式蒸发系统的工艺流程：碱浓缩、蒸汽、冷凝液流程，并对板式蒸发器的结构、装置特点及操作注意事项进行了叙述。     

硫化钠生产工艺的研究与改进

介绍在煤粉还原芒硝法基础上制备硫化钠,采用国家专利新型板式蒸发器进行浓缩,改进了生产工艺,使产品在质量、成本、能耗等各个方面的经济技术指标达到或超过国家标准和国际标准,综合效益比列管式蒸发器高出23 1%,建设投资低于列管式蒸发器 47%。     

Method to Characterize the Air Flow and Water Removal Characteristics during Vacuum Dewatering. Part I—Experimental Method

An experimental method using a novel design to characterize the air flow and water removal during vacuum dewatering in paper manufacturing is discussed. The experimental setup involves the intermittent application of vacuum, similar to commercial systems, using a rotating disk with slot opening arrangement. The system is capable of commercially realistic residence times of the order of milliseconds. The intermittent application of vacuum simulates vacuum dewatering on commercial paper machines. The air flow rate is calculated from changes in pressure and temperature in the vacuum tank underneath the sample. The role and importance of air flow during vacuum dewatering is studied by accurately measuring the air flow, properly taking into account the leaks during vacuum dewatering. The method described here provides for the first time accurate air flow and water removal data during vacuum dewatering. Methods of analysis of the experimental data are also presented. This information can be used to better understand the water removal process as well the role and importance of air flow during vacuum dewatering.     

Method to Characterize the Air Flow and Water Removal Characteristics during Vacuum Dewatering. Part I—Experimental Method

An experimental method using a novel design to characterize the air flow and water removal during vacuum dewatering in paper manufacturing is discussed. The experimental setup involves the intermittent application of vacuum, similar to commercial systems, using a rotating disk with slot opening arrangement. The system is capable of commercially realistic residence times of the order of milliseconds. The intermittent application of vacuum simulates vacuum dewatering on commercial paper machines. The air flow rate is calculated from changes in pressure and temperature in the vacuum tank underneath the sample. The role and importance of air flow during vacuum dewatering is studied by accurately measuring the air flow, properly taking into account the leaks during vacuum dewatering. The method described here provides for the first time accurate air flow and water removal data during vacuum dewatering. Methods of analysis of the experimental data are also presented. This information can be used to better understand the water removal process as well the role and importance of air flow during vacuum dewatering.     

新型减压裤型转油线设计在锦州石化常减压装置的应用

常减压装置原油经过减压炉加热后经过减压转油线输送至减压塔。减压转油线是包括主管段、分支段、过渡段和末端炉管在内的一个管系整体。减压转油管道的布置和安装需要综合考虑管道的压降、温降和流速等多方面因素影响,是常减压装置设计安装的难点和关键点。减压转油线的优化设计对提高减压炉油品拔出率和降低炉管油气出口温度提供了切实有效的方法,而且大幅度改善了油品质量、切实提高了油品稳定性,并有效避免了油品的超温裂解。锦州石化公司一套常减压装置改造设计中转油线主管段采用低速转油线,最大限度的降低了转油线的温降、压降;提高了减压塔的真空度,减压塔侧线拔出率大大提高,装置运行平稳,为锦州石化公司创造了相当可观的经济效益。     

真空玻璃传导和对流传热机理研究

利用传导和对流传热原理,建立了真空玻璃热量的流动和传递数学模型,推导了真空玻璃自由分子状态的导热量、支撑柱及边料的固体导热及真空玻璃的外表对流换热方程.分析了自由对流传热、纯气体、稀薄气体、支撑柱及边料的固体导热机理,探讨了真空玻璃的外表对流换热问题.研究结果表明,在低真空状态下的真空玻璃夹层厚度越小,越有利于由自由对流向纯气体导热方向发展,越有利于真空玻璃传热系数的降低.真空玻璃结构只要保持夹层真空度小于0.313 Pa就使得夹层内成为自由分子导热状态.     

基于ANSYS真空平板玻璃的动力学模态分析

利用大型有限元分析软件ANSYS对真空平板玻璃结构进行模态分析,按照真空玻璃国家标准,建立1000mm×1000mm真空平板玻璃模型,在ANSYS中设置材料属性及边界条件进行模态分析,在0～100000Hz频率范围内求解其1～10阶整体结构的固有频率及振型。另外,对相同尺寸下普通玻璃及中空玻璃模型进行模态分析,与真空平板玻璃固有频率及振型加以对比。结果表明:与普通平板玻璃及中空玻璃相比,真空平板玻璃每一阶固有频率最大,并且变形最小。说明真空平板玻璃刚度性能优先于普通玻璃及中空玻璃。为其整体设计及其制造提供了科学的依据,将有效预估结构的振动特性。     

活性炭负载醋酸锌催化剂真空干燥的特性

通过真空干燥实验研究了供热温度、真空度、料层厚度等因素对醋酸锌-活性炭催化剂干燥规律的影响。实验结果表明:醋酸锌-活性炭催化剂采用真空干燥可以实现快速低温干燥;催化剂的干燥只有降速干燥阶段,而没有常速干燥阶段;供热温度的提高有助于提高干燥速率,但温度超过80℃时催化剂出现轻微粉化;真空度越高,干燥速率特别是初始干燥速率越快;料层厚度的增加,使干燥时间延长,但设备的干燥强度有所提高。正交实验得出,在多因素条件下,温度对干燥强度的影响最大,其次是真空度和料层厚度。     

软质石蜡的研制

对利用南阳石蜡生产过程的副产品蜡下油制取软质石蜡的工艺条件进行了研究。研究表明,利用混合溶剂在一定条件下对蜡下油进行脱油可以研制软质石蜡,减二线蜡下油、减三线蜡下油研制软质石蜡最佳溶剂组成为酮65%、苯35%;减四线蜡下油研制软质石蜡最佳溶剂组成为60%、苯40%。在二段脱油工艺条件下,利用减二、减三、减四线蜡下油制得...     

Dewatering effect of vacuum preloading incorporated with electro-osmosis in different ways

The dredger fill dewatering effect of vacuum preloading incorporated with electro-osmosis in different ways was evaluated by implementing six laboratory tests. The results of these tests show that the asynchronous consolidation effect of vacuum preloading incorporated with electro-osmosis was better than the other tests. However, vacuum preloading and electro-osmosis will not be able to give full play to the drainage effect, if the alternate time is too short. Alternatively, the energy provided by vacuum preloading and electro-osmosis will not be able to make full use, if the alternate time is too long. There are some advantages when using vacuum preloading and electro-osmosis asynchronous reinforcement. The alternate time of vacuum preloading and electro-osmosis has to constantly adjust according to the water discharge or drainage rate in engineering application.     

Design of a multi-walled carbon nanotube field emitter with micro vacuum gauge

The variation of vacuum level inside a field emission device when electron is emitted from multi-walled carbon nanotubes (MWCNTs) by electric field was measured where MWCNT gauge packaged with a vacuum device was used to measure the degree of a vacuum until the end of the vacuum device life. It was found that the electrical properties of MWCNTs altered with the degree of a vacuum. We fabricated MWCNT gauge which were printed and pasted by the screen printer. In this paper, we report the successful detection of the ionization of gases in vacuum state.     

机械抽真空系统在减压蒸馏装置中的应用

在过去与现代的减压蒸馏装置中,具备一、二、三级抽空器的蒸汽抽真空系统始终占据着主导地位。而近年,一种新型的抽真空系统——机械抽真空系统正在慢慢地改变传统的抽真空方式。相对于传统的蒸汽抽真空系统,它的出现和逐步应用将会引领一场减压蒸馏中划时代的变革,通过对这两种抽真空方法的比较,浅析两种方法在减压蒸馏装置中的应用情况。